this bug has been reported 8 months ago, and i think it becomes more important to fix it now with all the filters that have been added, as toggling modes becomes vital to avoid Inkscape slowing down too much during design and still having a fast glimpse on the actual render.

The keyboard toggle now has 4 modes in 0.48. I wasn't sure about the 3 state toggle, but 4 modes is definitely too much. I strongly believe a toggle should have two states. After extensive use, I can tell toggling multiple states results in wild cycling of the options especially when in many circumstances the modes don't seem to have visible effect on canvas. And I often go one stop too far when toggling, resulting in more frustration.

Having a two state toggle reflects my need to periodically go into outline mode when working on complex and CPU intensive artwork and selecting objects easier (no fill/stroke etc). The standard solution to the UI problem has been to shove another cusomizability into file>inkscape preferences which is already way too full.

I would like to hear feed back from print people as to how they are using the print preview, but I am guessing they depend on the preview to be active most of the time rather than toggling back and forward between normal and print preview. Similarly the no-filters view sounds like something you toggle because the performance with filters is too poor. Again, not something you toggle back and forward all the time. So judging from my own use pattern the outline mode is always the state to toggle to.

The other state would be one of the 3 remaining display modes and would be persistant. So if the view is 'no filters' toggling ctrl+kp5 will go to outline and back to no filters. If the display mode is set to 'print colors preview' toggling goes between that and outline.